The crash killed 11 people, including the bus driver. More than 200 people suffered injuries.

Investigators acknowledge the bus driver ignored the signals but they say earlier in the day, a garbage truck broke off the end of the wooden barrier.

The recording shows a garbage truck breaking the end of the wooden, red-and-white painted barrier hours before Tuesday's pre-dawn crash. It then shows a security guard waving drivers across despite signals warning of nearby trains.

The video also shows that the security guard left just minutes before the 6:23 a.m. accident, and that someone had stuck a pole in the barrier to keep it from blocking traffic. It then shows a flow of traffic driving under the partially lowered barrier moments before the bus driver gambled that he could make it across as well.